| PROTON RAY LIMITED | Private company limited by shares | Dissolved |
| PROTON LIMITED | Private company limited by shares | Dissolved |
| PROTON HK LIMITED | Private company limited by shares | Dissolved |
| PROTON LED LIMITED | Private company limited by shares | Live |
| Proton Limited | Private company limited by shares | Live |
| Joy Proton Limited | Private company limited by shares | Live |
| Proton Capital Limited | Private company limited by shares | Live |
| Proton Capital HK Limited | Private company limited by shares | Dissolved |
| PROTON ENTERPRISES LIMITED | Private company limited by shares | Dissolved |
| PROTON INGREDIENTS LIMITED | Private company limited by shares | Dissolved |
| PROTON VIEW LIMITED | Private company limited by shares | Dissolved |
| PROTONBASE LIMITED | Private company limited by shares | Dissolved |
| Protonbase HK Limited | Private company limited by shares | Live |
| PRO-TONE LIMITED | Private company limited by shares | Dissolved |
| PROTONG LIMITED | Private company limited by shares | Dissolved |
| PROTONIC HOLDINGS LIMITED | Private company limited by shares | Live |
| Protonic Labs Limited | | Live |
| PROTONICS LIMITED | Private company limited by shares | Dissolved |
| Protons (Asia) Limited | Private company limited by shares | Live |
| PROTONTEK INTERNATIONAL LIMITED | Private company limited by shares | Live |